946 resultados para tailandesa lineage


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To verify whether fluorescence in situ hybridization (FISH) of cells from the buccal epithelium could be employed to detect cryptomosaicism with a 45,X lineage in 46,XY patients. Samples of nineteen 46,XY healthy young men and five patients with disorders of sex development (DSD), four 45,X/46,XY and one 46,XY were used. FISH analysis with X and Y specific probes on interphase nuclei from blood lymphocytes and buccal epithelium were analyzed to investigate the proportion of nuclei containing only the signal of the X chromosome. The frequency of nuclei containing only the X signal in the two tissues of healthy men did not differ (p = 0.69). In all patients with DSD this frequency was significantly higher, and there was no difference between the two tissues (p = 0.38), either. Investigation of mosaicism with a 45,X cell line in patients with 46,XY DSD or sterility can be done by FISH directly using cells from the buccal epithelium.

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Trypsins and chymotrypsins are well-studied serine peptidases that cleave peptide bonds at the carboxyl side of basic and hydrophobic l-amino acids, respectively. These enzymes are largely responsible for the digestion of proteins. Three primary processes regulate the activity of these peptidases: secretion, precursor (zymogen) activation and substrate-binding site recognition. Here, we present a detailed phylogenetic analysis of trypsins and chymotrypsins in three orders of holometabolous insects and reveal divergent characteristics of Lepidoptera enzymes in comparison with those of Coleoptera and Diptera. In particular, trypsin subsite S1 was more hydrophilic in Lepidoptera than in Coleoptera and Diptera, whereas subsites S2-S4 were more hydrophobic, suggesting different substrate preferences. Furthermore, Lepidoptera displayed a lineage-specific trypsin group belonging only to the Noctuidae family. Evidence for facilitated trypsin auto-activation events were also observed in all the insect orders studied, with the characteristic zymogen activation motif complementary to the trypsin active site. In contrast, insect chymotrypsins did not seem to have a peculiar evolutionary history with respect to their mammal counterparts. Overall, our findings suggest that the need for fast digestion allowed holometabolous insects to evolve divergent groups of peptidases with high auto-activation rates, and highlight that the evolution of trypsins led to a most diverse group of enzymes in Lepidoptera.

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O objetivo deste trabalho foi determinar as características de qualidade da carne de suínos de diferentes linhagens genéticas, em diferentes pesos de abate. Neste estudo foram utilizados 88 suínos por linhagem, fêmeas e machos castrados, com idade e peso médio iniciais de 74 dias e 30kg, respectivamente, pertencentes a três linhagens genéticas distintas, designadas de AgroceresPic, Dalland e Seghers. A etapa experimental foi dividida em quatro fases (Crescimento I, Crescimento II, Terminação I e Terminação II). Ao final de cada etapa, foram abatidos 60 animais (10 por linhagem/sexo), para as análises de qualidade da carne. O pH e a temperatura foram determinados a 1 e 24 horas post mortem. Foram retiradas amostras para as determinações de cor, perda de água por exsudação (PAE), perda de água por cocção (PAC) e força de Cisalhamento. As amostras provenientes das carcaças dos animais da linhagem AgroceresPic e Dalland apresentaram valores médios de PAE superiores aos da linhagem Seghers. Os valores médios de PAC foram diferentes entre as diferentes fases. Na fase Crescimento II, as carnes provenientes das carcaças das fêmeas Dalland foram mais duras, ou seja, com maiores valores de força de cisalhamento, que as carnes dos machos. Entretanto, na linhagem Seghers, as carnes dos machos foram mais duras. Observou-se diferença de L* entre os sexos da linhagem AgroceresPic nas fases Terminação I e II e, na linhagem Dalland, na Terminação II. As linhagens Dalland e Seghers apresentaram carnes com resultados superiores de a*, parâmetro característico da cor vermelha (a*>0). Pode-se concluir, portanto, que as características de qualidade da carne de suínos (pH, perda de água por exsudação, cor e maciez) podem variar entre grupos genéticos, entre sexos e entre diferentes pesos ao abate.

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Since the discovery of Trypanosoma cruzi and the brilliant description of the then-referred to "new tripanosomiasis" by Carlos Chagas 100 years ago, a great deal of scientific effort and curiosity has been devoted to understanding how this parasite invades and colonises mammalian host cells. This is a key step in the survival of the parasite within the vertebrate host, and although much has been learned over this century, differences in strains or isolates used by different laboratories may have led to conclusions that are not as universal as originally interpreted. Molecular genotyping of the CL-Brener clone confirmed a genetic heterogeneity in the parasite that had been detected previously by other techniques, including zymodeme or schizodeme (kDNA) analysis. T. cruzi can be grouped into at least two major phylogenetic lineages: T. cruzi I, mostly associated with the sylvatic cycle and T. cruzi II, linked to human disease; however, a third lineage, T. cruziIII, has also been proposed. Hybrid isolates, such as the CL-Brener clone, which was chosen for sequencing the genome of the parasite (Elias et al. 2005, El Sayed et al. 2005a), have also been identified. The parasite must be able to invade cells in the mammalian host, and many studies have implicated the flagellated trypomastigotes as the main actor in this process. Several surface components of parasites and some of the host cell receptors with which they interact have been described. Herein, we have attempted to identify milestones in the history of understanding T. cruzi- host cell interactions. Different infective forms of T. cruzi have displayed unexpected requirements for the parasite to attach to the host cell, enter it, and translocate between the parasitophorous vacuole to its final cytoplasmic destination. It is noteworthy that some of the mechanisms originally proposed to be broad in function turned out not to be universal, and multiple interactions involving different repertoires of molecules seem to act in concert to give rise to a rather complex interplay of signalling cascades involving both parasite and cellular components.

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We describe and illustrate the venom apparatus and other morphological characters of the recently described Martialis heureka ant worker, a supposedly specialized subterranean predator which could be the sole surviving representative of a highly divergent lineage that arose near the dawn of ant diversification. M. heureka was described as the single species of a genus in the subfamily, Martialinae Rabeling and Verhaagh, known from a single worker. However because the authors had available a unique specimen, dissections and scanning electron microscopy from coated specimens were not possible. We base our study on two worker individuals collected in Manaus, AM, Brazil in 1998 and maintained in 70% alcohol since then; the ants were partially destroyed because of desiccation during transport to São Paulo and subsequent efforts to rescue them from the vial. We were able to recover two left mandibles, two pronota, one dismembered fore coxa, one meso-metapropodeal complex with the median and hind coxae and trochanters still attached, one postpetiole, two gastric tergites, the pygidium and the almost complete venom apparatus (lacking the gonostylus and anal plate). We illustrate and describe the pieces, and compare M. heureka worker morphology with other basal ant subfamilies, concluding it does merit subfamilial status.

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To observe the effects of the parasitic infection on the biology of B. tenagophila, field and laboratory populations of this mollusk from Itariri, in Vale do Ribeira, Brazil, were experimentally infected. Each mollusk received 10 miracidia of Schistosoma mansoni (SJ lineage) and was observed throughout the parasite's development. The biological variables were compared according to the criteria "group" and "infectious phase". The main damage caused by the parasitic infection manifested itself in reproduction, longevity and lesions on the shell of the mollusks in the patent phase. An infection rate of 58.8% was observed. Microanatomical study of the mollusk's digestive gland and ovotestis revealed the presence of evolving larval forms and cercariae. It was concluded that the effects of the parasitic infection on both populations were moderate, despite the low survival rate of the infected mollusks, the damage did not prevent either reproduction or the elimination of cercariae, which continued for a long time.

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The detection of minimal residual disease (MRD) is an important prognostic factor in childhood acute lymphoblastic leukemia (ALL) providing crucial information on the response to treatment and risk of relapse. However, the high cost of these techniques restricts their use in countries with limited resources. Thus, we prospectively studied the use of flow cytometry (FC) with a simplified 3-color assay and a limited antibody panel to detect MRD in the bone marrow (BM) and peripheral blood (PB) of children with ALL. BM and PB samples from 40 children with ALL were analyzed on days (d) 14 and 28 during induction and in weeks 24-30 of maintenance therapy. Detectable MRD was defined as > 0.01% cells expressing the aberrant immunophenotype as characterized at diagnosis among total events in the sample. A total of 87% of the patients had an aberrant immunophenotype at diagnosis. On d14, 56% of the BM and 43% of the PB samples had detectable MRD. On d28, this decreased to 45% and 31%, respectively. The percentage of cells with the aberrant phenotype was similar in both BM and PB in T-ALL but about 10 times higher in the BM of patients with B-cell-precursor ALL. Moreover, MRD was detected in the BM of patients in complete morphological remission (44% on d14 and 39% on d28). MRD was not significantly associated to gender, age, initial white blood cell count or cell lineage. This FC assay is feasible, affordable and readily applicable to detect MRD in centers with limited resources.

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A morphological and cell culture study from nasal mucosa of dogs was performed in order to establish a protocol to obtain a cell population committed to neuronal lineage, as a proposal for the treatment of traumatic and degenerative lesions in these animals, so that in the future these results could be applied to the human species. Twelve mongrel dogs of 60-day aged pregnancy were collected from urban pound dogs in São Paulo. Tissue from cribriform ethmoidal lamina of the fetuses was collected at necropsy under sterile conditions around 1h to 2h postmortem by uterine sections and sections from the fetal regions described above. Isolated cells of this tissue were added in DMEM/F-12 medium under standard conditions of incubation (5% CO², >37ºC). Cell culture based on isolated cells from biopsies of the olfactory epithelium showed rapid growth when cultured for 24 hours, showing phase-bright sphere cells found floating around the fragments, attached on culture flasks. After 20 days, a specific type of cells, predominantly ellipsoids or fusiform cells was characterized in vitro. The indirect immunofluorescence examination showed cells expressing markers of neuronal precursors (GFAP, neurofilament, oligodendrocyte, and III â-tubulin). The cell proliferation index showed Ki67 immunostaining with a trend to label cell groups throughout the apical region, while PCNA immunostaining label predominantly cell groups lying above the basal lamina. The transmission electron microscopy from the olfactory epithelium of dogs revealed cells with electron-dense cytoplasm and preserving the same distribution as those of positive cell staining for PCNA. Metabolic activity was confirmed by presence of euchromatin in the greatest part of cells. All these aspects give subsidies to support the hypothesis about resident progenitor cells among the basal cells of the olfactory epithelium, committed to renewal of these cell populations, especially neurons.

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As origens e distribuições das artérias que vascularizaram os lobos torácicos do timo foram estudadas em fetos de 30 suínos da linhagem C40, sendo 12 machos e 18 fêmeas. Os exemplares tiveram o sistema arterial preenchido com solução aquosa a 50% de Neoprene Látex corado e, em seguida, foram submetidos à fixação em solução aquosa a 10% de formaldeído. Os lobos torácicos do timo foram vascularizados por ramos diretos das artérias torácica interna direita (63,33%) e esquerda (53,33%), subclávia esquerda (3,33%), vertebral esquerda (3,33%), cervical superficial direita (3,33%) e esquerda (3,33%), carótida comum esquerda (3,33%), coronária direita (3,33%) e pelos troncos braquiocefálico (33,33%) e costocervical (3,33%). Observaram-se ainda os ramos indiretos das artérias torácica interna direita (70%) e esquerda (76,67%), subclávia esquerda (23,33%), cervical superficial esquerda (3,33%) e do arco aórtico (6,67%).

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As características morfológicas, macroscópicas e microscópicas, dos órgãos genitais masculinos e da cloaca foram analisados em 23 emas, quatro filhotes (duas semanas), sete jovens (de três a oito meses) e doze adultos (três anos), provenientes da Cooperativa Emas do Brasil, RS, e do CEMAS, Mossoró, RN. Os testículos da ema possuem formato alongado e localizam-se na cavidade celomática, na região intra-abdominal dorsal, com comprimento e larguras médias de 7,6±1,2cm e 2,6± 0,7cm nos adultos; 4,5±1,5cm e 0,9±0,4cm nos jovens; e 0,8±0,3cm, e 0,2±0,1cm nos filhotes. O testículo está envolto pela túnica albugínea e seu parênquima possui túbulos seminíferos irregulares, compostos por epitélio espermatogênico e por células de sustentação, e pelo tecido intersticial, com as células endócrinas intersticiais, tecido conjuntivo frouxo e vasos. Nos adultos observaram-se todas as células da linhagem espermatogênica, enquanto nos jovens com 3 meses, os testículos apresentaram túbulos seminíferos com luz reduzidas, espermatogônias e células de sustentação indiferenciadas. Os ductos eferentes possuem um epitélio cúbico ciliado, enquanto no ducto epididimário o epitélio é columnar. O epidídimo apresentou-se alongado e fusiforme junto a margem medial do testículo. O ducto deferentes apresentou trajeto sinuoso nos adultos, retilíneo nos jovens, convoluto na sua porção média, diminuindo seu formato sigmóide em sua porção caudal, próximo à cloaca. O epitélio é pseudoestratificado e reveste a luz irregular nos adultos e circular nos jovens, mantendo proximidade com o ureter. A cloaca dividiu-se em três segmentos: o coprodeu, o urodeo e o proctodeo. No urodeu os ductos deferentes desembocaram em papilas na parede ventro-lateral, próximo a inserção do falo fibroso. O falo é um órgão fibroso linfático, localizado na parede ventral, no assoalho da cloaca, e apresentou duas porções: uma rígida bifurcada e contorcida, e outra simples espiralada e flexível, a qual normalmente esteve invertida. Em exposição forçada, o falo teve 14 cm de comprimento. De forma geral os órgãos reprodutores das emas compartilharam da morfologia de outras aves, principalmente aquelas descritas para os avestruzes.

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A vascularização arterial do timo (número, origem e ordenação) bem como a distribuição parenquimal dos ramos penetrantes foram estudadas em 40 aves da linhagem Paraíso Pedrês. Trinta aves foram injetadas com látex e dissecadas, enquanto 10 aves tiveram seus sistemas arteriais injetados com resina (metil metacrilato e mercox) para a preparação de moldes vasculares. A principal fonte de irrigação encontrada foi a associação dos ramos oriundos das artérias comuns do nervo vago, tireóideas e ingluviais, sendo que seus ramos penetravam o parênquima dos lobos, principalmente pelas suas extremidades cranial e caudal. A partir da penetração, os ramos tímicos apresentavam distribuição predominante para a periferia do lobo, formando uma trama capilar poligonal, com espaços irregulares, característica de um órgão linforreticular.

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This article reports on the identification of a group 2 coronavirus (BatCoV DR/2007) in a Desmodus rotundus vampire bat in Brazil. Phylogenetic analysis of ORF1b revealed that BatCoV DR/2007 originates from a unique lineage in the archetypical group 2 coronaviruses, as described for bat species elsewhere with putative importance in Public Health.

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Com objetivo de observar os efeitos da infecção parasitária na biologia de B. tenagophila, foram realizadas infecções experimentais em populações de campo e laboratório, ambas procedentes de Itariri, Vale do Ribeira, Brasil. Cada molusco recebeu 10 miracídios de Schistosoma mansoni (linhagem SJ), sendo observado durante o desenvolvimento dos parasitos. As variáveis biológicas foram comparadas segundo os critérios "grupo" e "fase de infecção". Os principais danos decorrentes do parasitismo se manifestaram na reprodução, na longevidade e em lesões na concha dos moluscos na fase patente. Foi encontrada uma taxa de infecção de 58,8 por cento. O estudo microanatômico da glândula digestiva e do ovoteste do molusco revelou a presença de formas larvárias em evolução e cercárias. Concluiu-se que os efeitos da infecção parasitária, sobre as duas populações, foram moderados, uma vez que os danos não impediram a reprodução e a eliminação de cercárias que se manteve por um longo período, apesar da baixa sobrevivência dos moluscos parasitados

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Understanding why we age is a long-lived open problem in evolutionary biology. Aging is prejudicial to the individual, and evolutionary forces should prevent it, but many species show signs of senescence as individuals age. Here, I will propose a model for aging based on assumptions that are compatible with evolutionary theory: i) competition is between individuals; ii) there is some degree of locality, so quite often competition will be between parents and their progeny; iii) optimal conditions are not stationary, and mutation helps each species to keep competitive. When conditions change, a senescent species can drive immortal competitors to extinction. This counter-intuitive result arises from the pruning caused by the death of elder individuals. When there is change and mutation, each generation is slightly better adapted to the new conditions, but some older individuals survive by chance. Senescence can eliminate those from the genetic pool. Even though individual selection forces can sometimes win over group selection ones, it is not exactly the individual that is selected but its lineage. While senescence damages the individuals and has an evolutionary cost, it has a benefit of its own. It allows each lineage to adapt faster to changing conditions. We age because the world changes.

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Aspergillus fumigatus is a common mould whose spores are a component of the normal airborne flora. Immune dysfunction permits developmental growth of inhaled spores in the human lung causing aspergillosis, a significant threat to human health in the form of allergic, and life-threatening invasive infections. The success of A. fumigatus as a pathogen is unique among close phylogenetic relatives and is poorly characterised at the molecular level. Recent genome sequencing of several Aspergillus species provides an exceptional opportunity to analyse fungal virulence attributes within a genomic and evolutionary context. To identify genes preferentially expressed during adaptation to the mammalian host niche, we generated multiple gene expression profiles from minute samplings of A. fumigatus germlings during initiation of murine infection. They reveal a highly co-ordinated A. fumigatus gene expression programme, governing metabolic and physiological adaptation, which allows the organism to prosper within the mammalian niche. As functions of phylogenetic conservation and genetic locus, 28% and 30%, respectively, of the A. fumigatus subtelomeric and lineage-specific gene repertoires are induced relative to laboratory culture, and physically clustered genes including loci directing pseurotin, gliotoxin and siderophore biosyntheses are a prominent feature. Locationally biased A. fumigatus gene expression is not prompted by in vitro iron limitation, acid, alkaline, anaerobic or oxidative stress. However, subtelomeric gene expression is favoured following ex vivo neutrophil exposure and in comparative analyses of richly and poorly nourished laboratory cultured germlings. We found remarkable concordance between the A. fumigatus host-adaptation transcriptome and those resulting from in vitro iron depletion, alkaline shift, nitrogen starvation and loss of the methyltransferase LaeA. This first transcriptional snapshot of a fungal genome during initiation of mammalian infection provides the global perspective required to direct much-needed diagnostic and therapeutic strategies and reveals genome organisation and subtelomeric diversity as potential driving forces in the evolution of pathogenicity in the genus Aspergillus.